Tumor Necrosis Factor-α Increases Circulating Osteoclast Precursor Numbers by Promoting Their Proliferation and Differentiation in the Bone Marrow through Up-regulation of c-Fms Expression*

Osteoclasts are essential cells for bone erosion in inflammatory arthritis and are derived from cells in the myeloid lineage. Recently, we reported that tumor necrosis factor-α (TNFα) increases the blood osteoclast precursor (OCP) numbers in arthritic patients and animals, which are reduced by anti-TNF therapy, implying that circulating OCPs may have an important role in the pathogenesis of erosive arthritis. The aim of this study is to investigate the mechanism by which TNFα induces this increase in OCP frequency. We found that TNFα stimulated cell division and conversion of CD11b+/Gr-1-/lo/c-Fms- to CD11b+/Gr-1-/lo/c-Fms+ cells, which was not blocked by neutralizing macrophage colony-stimulating factor (M-CSF) antibody. Ex vivo analysis of monocytes demonstrated the following: (i) blood CD11b+/Gr-1-/lo but not CD11b-/Gr-1- cells give rise to osteoclasts when they were cultured with receptor activator NF-κB ligand and M-CSF; and (ii) TNF-transgenic mice have a significant increase in blood CD11b+/Gr-1-/lo cells and bone marrow proliferating CD11b+/Gr-1-/lo cells. Administration of TNFα to wild type mice induced bone marrow CD11b+/Gr-1-/lo cell proliferation, which was associated with an increase in CD11b+/Gr-1-/lo OCPs in the circulation. Thus, TNFα directly stimulates bone marrow OCP genesis by enhancing c-Fms expression. This results in progenitor cell proliferation and differentiation in response to M-CSF, leading to an enlargement of the marrow OCP pool. Increased marrow OCPs subsequently egress to the circulation, forming a basis for elevated OCP frequency. Therefore, the first step of TNF-induced osteoclastogenesis is at the level of OCP genesis in the bone marrow, which represents another layer of regulation to control erosive disease.

[1]  Y. Kadono,et al.  Osteoclast differentiation independent of the TRANCE–RANK–TRAF6 axis , 2005, The Journal of experimental medicine.

[2]  E. Schwarz,et al.  Tumor necrosis factor prevents alendronate-induced osteoclast apoptosis in vivo by stimulating Bcl-xL expression through Ets-2. , 2005, Arthritis and rheumatism.

[3]  Matthew J. Silva,et al.  Marrow Stromal Cells and Osteoclast Precursors Differentially Contribute to TNF-α-Induced Osteoclastogenesis In Vivo1 , 2004, The Journal of Immunology.

[4]  E. Schwarz,et al.  RANK Signaling Is Not Required for TNFα‐Mediated Increase in CD11bhi Osteoclast Precursors but Is Essential for Mature Osteoclast Formation in TNFα‐Mediated Inflammatory Arthritis , 2003, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[5]  S. Teitelbaum,et al.  Genetic regulation of osteoclast development and function , 2003, Nature Reviews Genetics.

[6]  Steffen Jung,et al.  Blood monocytes consist of two principal subsets with distinct migratory properties. , 2003, Immunity.

[7]  S. Goldring,et al.  Inflammatory Mediators as Essential Elements in Bone Remodeling , 2003, Calcified Tissue International.

[8]  David L. Lacey,et al.  Osteoclast differentiation and activation , 2003, Nature.

[9]  E. Schwarz,et al.  Exposure to receptor-activator of NFκB ligand renders pre-osteoclasts resistant to IFN-γ by inducing terminal differentiation , 2002, Arthritis research & therapy.

[10]  R. T. Sjin,et al.  Transcriptional regulation of myeloid differentiation primary response (MyD) genes during myeloid differentiation is mediated by nuclear factor Y. , 2002, Blood.

[11]  Ulrich Siebenlist,et al.  NF‐κB p50 and p52 Expression Is Not Required for RANK‐Expressing Osteoclast Progenitor Formation but Is Essential for RANK‐ and Cytokine‐Mediated Osteoclastogenesis , 2002, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[12]  C. Dreezen,et al.  Rheumatological complications associated with the use of indinavir and other protease inhibitors , 2002, Annals of the rheumatic diseases.

[13]  F. Carlotti,et al.  Bcl-xL Expression Correlates with Primary Macrophage Differentiation, Activation of Functional Competence, and Survival and Results from Synergistic Transcriptional Activation by Ets2 and PU.1* , 2001, The Journal of Biological Chemistry.

[14]  S. Takeshita,et al.  TNF-alpha induces osteoclastogenesis by direct stimulation of macrophages exposed to permissive levels of RANK ligand. , 2000, The Journal of clinical investigation.

[15]  R. Pacifici,et al.  Estrogen deficiency induces bone loss by enhancing T-cell production of TNF-alpha. , 2000, The Journal of clinical investigation.

[16]  I. Weissman,et al.  A clonogenic common myeloid progenitor that gives rise to all myeloid lineages , 2000, Nature.

[17]  Kangsheng Wang,et al.  Quantitation of dihydropyrimidine dehydrogenase expression by real-time reverse transcription polymerase chain reaction. , 2000, Analytical biochemistry.

[18]  T. Miyata,et al.  Commitment and Differentiation of Osteoclast Precursor Cells by the Sequential Expression of C-Fms and Receptor Activator of Nuclear Factor κb (Rank) Receptors , 1999, The Journal of experimental medicine.

[19]  J. Cashman,et al.  Differentiation stage-specific regulation of primitive human hematopoietic progenitor cycling by exogenous and endogenous inhibitors in an in vivo model. , 1999, Blood.

[20]  Josef M. Penninger,et al.  Activated T cells regulate bone loss and joint destruction in adjuvant arthritis through osteoprotegerin ligand , 1999, Nature.

[21]  G D Roodman,et al.  Cell biology of the osteoclast. , 1999, Experimental hematology.

[22]  S. Mckercher,et al.  Myeloid Development Is Selectively Disrupted in PU.1 Null Mice , 1998 .

[23]  R. Pyatt,et al.  Functional Heterogeneity of Human CD34+ Cells Isolated in Subcompartments of the G0 /G1 Phase of the Cell Cycle , 1997 .

[24]  R. Shackelford,et al.  Tumor Necrosis Factor-α Inducesc-fmsRNA Expression in Murine Tissue Macrophages , 1997 .

[25]  J. Rubin,et al.  Macrophage Colony Stimulating Factor Down‐Regulates MCSF‐Receptor Expression and Entry of Progenitors into the Osteoclast Lineage , 1997, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[26]  E. Jimi,et al.  Regulation of Osteoclast Function , 1997, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[27]  M. Horowitz,et al.  Tumor necrosis factor‐α induces transcription of the colony‐stimulating factor‐1 gene in murine osteoblasts , 1996, Journal of cellular physiology.

[28]  D. Kioussis,et al.  Transgenic mice expressing human tumour necrosis factor: a predictive genetic model of arthritis. , 1991, The EMBO journal.

[29]  L. E. Schwarz Circulating Osteoclast Precursors: A Mechanism and a Marker of Erosive Arthritis , 2005 .

[30]  E. Schwarz,et al.  Systemic tumor necrosis factor α mediates an increase in peripheral CD11bhigh osteoclast precursors in tumor necrosis factor α–transgenic mice , 2004 .